‘Theory becomes possible only if various objects and processes, movements and events, acts and interactions are viewed as forming a domain that can be studied in its own right” (Waltz, 1995: 69).
This is a positivist statement. The identification of a domain within wider reality is a clear positivist step. Only if we cut out a section of reality and hold its borders as constant, can we think in terms of identifying regular causal relationships in an objective reality separate from us as researcher.